The present invention relates to the mobile communication receivers and more specifically to a multiple-mode mobile communication receiver capable of processing signals of distinct communication standards.
As different competing standards of mobile communications become available, there is an increasing need for devices capable of operating with multiple communication standards. Such “multiple-mode” devices are able to communicate with using one standard at a particular time, and switch to operate using another standard at another time as needed.
FIG. 1 illustrates the basic concept of “multiple-mode” operation. A mobile device 102 is capable of communicating with a first base station 104 and a second base station 106, which are built for different standards of communication. At some point in time, the mobile device 102 communicates with the base station 104, using a first communication standard. At another point in time, the mobile device switches its operation to communicate with the second base station, using a second communication standard. Thus, as the device 102 has an increased range of operation, because it is able to communicate while within the coverage area of base stations using the first communication standard as well the coverage area of base stations using the second communication standard.
Multiple-mode devices such as the one described above have been built using various designs. One design is simply to combine what are essentially two or more separate devices, each capable of communication using a different standard. Other designs have also attempted to combine such separate devices, but with some resources being shared between the separate devices. Such sharing of resources allows improvements in size, cost, power consumption, and/or other considerations.
However, as newer communication standards are developed, more complex and specialized implementations of advanced standards make it especially challenging to find feasible solutions for efficiently combining inherently dissimilar devices. Specifically, one increasingly popular communication standard is generally referred to as Global System for Mobile Communications (GSM). The GSM standard includes 2.5G, 3G, EGSM, EDGE, GPRS, and others. Another increasingly popular communication standard is generally referred to as wide band code division multiple access (WCDMA). The WCDMA standard includes UMTS, CDMA, and others.
Thus, there is a need for an improved strategy for building multiple-mode devices capable of supporting more than one of the more advanced communication standards, such as GSM and WCDMA, that accommodates different implementations required by such standards.